温度/溶剂双梯度高效液相色谱法测定环境空气中的羰基化合物

摘要

该文建立了环境空气中13种碳数在1～8范围内的羰基化合物（6种脂肪醛、2种芳香醛、3种不饱和醛和2种酮）的温度/溶剂双梯度2，4-二硝基苯肼衍生/高效液相色谱分析方法。通过选择合适的色谱柱，优化柱温，用水和乙腈两元溶剂梯度基线分离了13种羰基化合物的衍生物。利用温度梯度解决了13种羰基化合物中C3组分（丙烯醛、丙酮和丙醛）和C4组分（丁烯醛、甲基丙烯醛、丁酮和正丁醛）难以分离的问题。优化的方法在各自的浓度范围内线性相关系数良好（r≥0.9999）；对于50.0L的空气样品检出限在0.04～0.19μg/m3（以羰基化合物计）；该方法的相对标准偏差小于3.6%；加标回收率在95%～106%，适用于环境空气中羰基化合物的测定。%A sensitive method based on derivatization with 2,4-dinitrophenylhydrazine(DNPH)followed by temperature/organic solvent double-gradient high performance liquid chromatography analysis of 13 carbonyl compounds(6 aliphatic,2 aromatic and 3 unsaturated aldehydes and 2 ketones)in ambient air was devel⁃oped.Chromatographic conditions including chromatographic column,column temperature,and detection wave⁃length were investigated so that the separation was carried out on gradient elution using two solvents(water and acetonitrile). The problem that the C3 series(acrolein-DNPH,acetone-DNPH and propionaldehyde-DNPH)and C3 series(crotonaldehyde-DNPH,methacrolein-DNPH,2-butanone-DNPH and butyraldehyde-DNPH)in 13 carbonyl compounds were difficlut to separate were solved using temperature gradient.The opti⁃mized method has been validated when rectilinear relationship was obtained between the concentrations of analytes and peak area,and the correlation coefficients were ≥0.999 9. The limits of detection for air sam⁃ples of 50.0 L varied between 0.04~0.19μg/m3 expressed as carbonyl.The method relative standard devia⁃tions(%RSD)of all applied carbonyls were lower than 3.6%,and spiked recoveries were in the range of 95%~106%. The method was applied to monitor the concentration of carbonyl compounds in ambient air.